1. Field of the Invention
This invention relates to a three-cable remote control mechanism and particularly to such a mechanism adaptable for controlling from the interior of an automotive vehicle a rear-view mirror mounted outside of the passenger compartment such as on the front fender or door panel of the vehicle.
2. Prior Art
A variety of remote control rear-view assembly forms and constructions have been known for automobile and other similar usages. Particularly, those of the three-cable-operated type are extremely common, which typically comprises a mirror assembly (controlled unit) mounted in some convenient location outside of an automobile, and an actuator assembly (controlling unit) mounted in a convenient position within the driver's compartment and adapted for selectively positioning and retaining in position the mirror assembly, there being provided a plurality of flexible operating cables, usually three in number, with which to interconnect the mirror or controlled assembly with the actuator or controlling assembly, and which is adapted for transmitting controlled movement from the actuator to the mirror to adjust the angle or position of the mirror glass.
Certain typical examples of such a three-cable-operated remote control device are shown for example in U.S. Pat. No. 2,931,245, U.S. Pat. No. 3,096,664 and U.S. Pat. No. 3,552,228. There is one technical aspect that these patents have in common; that is, there is provided resilient means such as a yieldable spring for imposing tension upon the cables to absorb the expansion and contraction thereof which may result from ambient temperature variations, from changes in the distance between the mirror assembly and the remotely located actuator assembly depending upon the type and form of automobiles, or from other dimensioned changes in the cable length during operation. The yieldable spring is disposed between a manually operable lever or handle with which to actuate the cables to adjust the position of the mirror and a bushing at the opposite end of the actuator housing, whereby the spring takes slack or relieves excess tension out of the cables. It readily occurs that response of the mirror to its associated control actuator is higher the greater the tension of the operating cables. However, when imposing tension upon the cables to this end, the spring pulls the actuator lever axially forwardly of the housing, sometimes too far forwardly, with the result that the lever cannot be manipulated for a desired universal pivotal movement due to physical interference by the bezel or nut that secures the actuator assembly to the mounting panel in the automobile interior. Therefore, the yieldable spring as arranged in the above prior art devices often tends to prohibit the free, proper adjustment of the position or reflecting angle of the mirror.
A study of the construction of U.S. Pat. No. 3,552,228 indicates that it has an additional drawback in that due to the arrangement in which the points of connection of the three operating cables at the control actuator must be oriented to be in exactly opposite relationship to those of the cables at the mirror in order to maintain the cojoint pivotal movement of the two units in the same direction, it becomes necessary to sort out individual actuator units for use with mirror units designed for mounting exclusively either at the right-hand side or the left-hand side of the automobile. In other words, if an actuator unit of a right-hand design was used with a mirror unit adapted to be mounted exclusively on the left-hand side of the automobile, then manipulation of the control lever in one or the forward direction would result in the pivotal movement of the mirror in the other or the reverse direction.